Обсуждение: pgsql: Update comments about index parallel builds

Update comments about index parallel builds

Commit b43757171470 allowed parallel builds for BRIN, but left behind
two comments claiming only btree indexes support parallel builds.

Reported by Egor Rogov, along with similar issues in SGML docs.
Backpatch to 17, where parallel builds for BRIN were introduced.

Reported-by: Egor Rogov
Backpatch-through: 17
Discussion: https://postgr.es/m/114e2d5d-125e-07d8-94aa-5ad175fb7443@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8cd44db42a40056a701a4ae03d73bf2cd05781b1

Modified Files
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src/backend/catalog/index.c          | 2 +-
src/backend/optimizer/plan/planner.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)